If there is no meaningful existence without God, then what is hell, in your opinion?

Are you saying that we couldn't make any choices without Lucifer?

Okay, so if I let my kid walk into moving traffic, even though I could stop him, then it's okay because it's his choice? Hell is absolutely punishment, as you describe it, because God keeps people alive forever when He doesn't have to. That makes it His choice to continue the torture, so if it's not punishment then it's just a psychopath torturing lesser beings. Would you stand by and watch your kid torture the dog for hours because it pissed in the house? How about days? Years? Decades?